X-ray cooling system



J. B. WANTZ X-RAY COOLING SYSTEM Filed May 10, 1924 MAWMasmr a w. M. k/

\NVENTOR 8. WHNTL JULHJS.

Patented Apr. 10,1928.

' UNITED STATES JULIUS 1B. WANTZ, OE OAK PARK, ILLINOIS, ASSIGNOR TO VICTOR x-BAY CORPORA- rron, or cmcaeo, ILLINOIS,

A CORPORATION OF ILLINOIS.

as. coomne 5mm.

Application filed May 10? 1924. Serial no. viaaae.

The invention herein disclosed and described has to do with X-ray apparatus and relates particularly to the structure thereof and to the provision of a. water-cooling system for the X-ray tube. In X-ray therapy, it is desirable to use apparatus in which tremendous energies are im osed for long periods of time upon the tu e, and various means for maintaining the tube against overheating have been proposed. A watercooling system has been found. to be most satisfactory but highly valuable tubes are repeatedly damaged or destroyed from defic 'ency inthe water-circulation. Tubes are now made with capacities of 250,000 volts.

and to 50 milliamperes, and with such energy imposed thereupon, perfection 1n a water cooling system is necessary for failure to function means almost instant destruc-' tion of the tube, but no means automatically controlled by the circulatory system have' directed through the tube are arrested. when quate, and secondarily, to employ a unique the watercooling system becomes inadearrangem'ent between the water cooling'system and the electrical connections leading tothe tube. j

These, and such other objects as may hereinafter appear are attained by the novel construction, arrangement and combination of elements, hereinafter described and fully illustrated in the accompanying drawing, 'herebymade a part of this specification, and in which Figure 1 is a perspective view of a water cooling system for an X-ray tube embodying'the invention, the wiring system associated with the X-raytube being schematicallyfshown; and

Figure 2 is a; detail of the thermostat and v the switch member controlled thereby. I

. Like referencecharacters are used to designate similar parts in the drawing and in the description which follows.

In Figure 1, the ordinals 11 and 12 indicate mains leading from a source of alternating current. A line switch 13 is disposed therein. A step-up transformer 14 has its primary winding in circuit with said mains through line 15 and line 16. In the latter tube.

fying s vitchz25 in circuit with the secondary of transformer 14, and for convenience, a hand-switch 26 is arranged upon the conduits leading .to said synchronous motor. The-h gh potential generated in the secondary of transformer 14, after rectification byswitch 25 into pulsating unidirectional current, is conveyed to an X-ray tube by con.-

X-ray tube.

The secondary current from transformer 21 is conveyed to the cathode of a tube 29 by conduits 30 and 31, the former being electrically connected to the conduit27from the high potential transformer 14. Conduits 27 and 31 are joined to forma cable 32, and wound upon a-reel 33, said'conduits' being electrically connected to the cathode terminals of tube 29.

' The target (anode) of the tube 29 is provided with a fluid conduit or passageway 'for 'circulating cooling water. A considerable volume of water is required for cooling the tube for the water is rapidly heated. Artificial cooling apparatus for the water is ator 34 to the pump 35, a flexible pipe 37 leaving a pressure gauge 38 disposed thereon and leading from the pump 35 tothe tube 29. and. as econd flexible pipe 39 con-.

veying the water back to radiator 34 through a'thermostat 40. Y The flexible pipes 37 and 39 are of electrically conducting material, and engage a also necessary. Such apparatus may in stirrup or guide 40" upon conduit 28, .to

establish electrical connection between. the high potential carried thereby and the anode of tube 29. No reel or cable, as is usual, is

7c duits 27 and 28, which, as indicated, may be parallel tube .members disposed above the v required for the anode conduit, for the flexible pipes or tubes just described are of sufficient resiliency and body to allow reasonably free movement thereof to make the revquircd connection with the tube 29.

Radiator 34 and pump 35 are disposed upon a platform 41 which forms one end of a frame having at its other end a motor base 42 upon which is mounted a motor 43, having an insulating shaft 44 for driving pump 35. Upon said insulating shaft 44 is also carried a fan 44 for forcing air through the cells of'radiator 34. intermediate base 42 and platform 41 are brace members 45, bar or tube like in character and of insulate ing material, and the entire frame is supported upon wall brackets 46 by standards 47 which may have at one or both ends bifurcated beads engaging the frame. Suitable conduits 48 and 49 lead to motor 43 from mains 11 and 12 and a line switch 50 is employed for manually controlling the current passing therethrough.

The thermostat 40 has a vertically reciprocating stem 51 adapted to rise with an-increase in temperature of the water in the circulatory system-or when no water circu lates therethrough. Stem 51 is' pivotally.

connected to one arm of a-lever 52 carried by a bracket 53 aflixed to radiator 34. To the other arm of lever 52 is movably attached a rod 54 of insulating material having at its outermost end a collar 55. When the temperature in the circulatory system rises, or

' no water circulates through the X-ray tube,

stem 51 actuates rod 54 to engage a movable contact 56 whereby to advance it toward and against a stationary contact'57. Rod 54 may be conveniently disposed in one of hollow brace member-s45 as indicated in figure 1. As movable contact 56 is brought into contact with fixed contact 57, the circuit in conduits 58 and 59; is closed. Resistance 60 is ordinarily placed in the circuit breaker circuit.

From the foregoing the operation of the device is apparent. High potential is enerated in transformer 14,- reetified in switch 25, and energizes tube 29. About the anode of said tube water circulates'to and from a radiator 34 which serves also as a supply tank forthe cooling media. when the cir-' culation is inadequate for suflielentcooling,

the temperature of the water rises. .Such

rise in temperature affects the thermostat 40 which actuates a no-voltage release 18,

t whereupon the circuit to the primary winding of transformer 14.is broken. Lack of circulating water also aetuates .saidrelease; Such deficiency causes the thermostat 40 to actuate no voltage release 18 for thermostat 40 may be retained in operable posi-.

tion only when the water in the circulatory system is in suflicient volume to adequately cool the anode and "is of such temperature voltage release 18, and conduit 12. As has been previously indicated, the contacts in the no-voltage release 16 are kept together only so long as there is a flow of clectromo tive force therethrough.

The high tension circuit is from one side of the secondary of the transformer" 14 to the rectifier 25, the conduit 28 to the tube 29, the conduit 27, the rectifier 25, and to the other side of the secondary of the trans former 14.

Conduits 11 and 12 are also used to energize synchronous'motor 24 adapted to ac The primary of the tuate the rectifier 25v and the motor 43 adapted to drive the pump and fan in the cooling apparatus. Indi idual switches 26 and 50 for said devices are provided.

Likewise,- the electromotive force, taken fromthe conduits 11 and 12. is adapted to energize the primary of the filament transformer 21. The secondary of said filament transformer 21, through the conduits 30 and 31, is adapted to energize or heat the filament of the X-ray tube 29.

VVhcn'the apparatus is operated normally,

conduits 11 and 12 supply electromotive force to energizethe no-voltage release 18 through the conduits 58 and 59, the conduit 58 having disposed therein a suitable resistance 60. Whenever overheating occurs, as has been previously described, the flow of electromo-' tive force is from the conduits 11 and 58 to the contacts 56 and 57, and'thence to conduit 59 and to conduit 12. This diverts the electromotive force normally flowin through the no-voltage' release 18 and res1stance'60,

to a path of less resistance, and permits the contacts on the voltage release 18 in conduit 16 to separate.

Thecycle of operation of the rectifier 25 is that usual in the well-known type of Snook rectifier, and is a type of rectification frequently employed for X-ray work,

Suitable switches 17 and 22 may be em ployed, respectively, in conduits. 16 and 19, a said switches and switches 13, 26 and 50,

being manually operated. F

The 0 eration of the thermostat disclosed in Figure 1 corresponds substantially to that illustrated in detail in. Figure 2 exceptthat contact is made by the ush method rather than the. pull meth The thermostat 4O Figure 1 is adapted III 156 connected with conduit 59. A fixed con-' tact 157 is shown adjacent the movable contact 156 just referred to and such fixed contact is electrically connected to conduit 58.

Movement of the insulating rod 154 as an incident tooverheating of the waterin the circulatory system causes the two contacts 156 and 157 just described to impinge whereby electromotive force may flow through conduits 58 and 59. The circuit established is 12, 59, 156, 157, 58, 60,'and 11 whereby the no-voltage release 18 ceases to function, opening the normally closed circuit comprising 12, 16, 1 1, 15, and 11. The opening of the circuit last referred to prevents the impression of electromotive force upon the'high tension transformer 14 and this, ofcourse, de-energizes the tube 29.

Many modifications in the specific type of this safety device are possible. The wiring schemes may be manifold. The apparatus may be wired to operate with a'direct current source of power. The spirit of the invention resides in the safety means whereby the overheating of a tube is employed to Whatis desired to be secured by Letters Patent of the United States is:

' 1. In combination, an electrical circuit for supplying power, means for shutting on such power, a secondary circuit for energiz ing an X-ray tube, a Water-cooled tube, and a cooling system for said tube comprising a pump, radiator, fan, and thermostat, said ,shut off the source of energy causing the overheating.

thermostat being adapted to terminate the flow of current in said first mentioned. circuit by actuating said shutting off means.

.1 2. The combination of an electrical circuit for supplying power, means for shutting off such power, a secondary circuit for energizing an X-raytube, and. a Water cooled tube, with a cooling system for'said tube comprising a pump, radiator, fan, and thermostat, said thermostat being adapted to terminate the flow of current in said firstmentioned circuit, by actuating said shutting ofl' meansand said pump and fan being coupled.

JULI S WANTZ. 

